The invention relates to umbrellas in general, and more particularly to improvements in umbrellas of the type wherein the collapsible canopy is suspended on a support.
A drawback of conventional umbrellas with a suspended canopy is that the wind is likely to sway and set in rotary motion the frame which carries the canopy as soon as the connection between the frame and the overhead support is relaxed. As a rule, the connection includes a joint which permits the canopy and its frame to turn and to thereby enable the canopy to descend as soon as the connection between the frame and the overhead support is relaxed. Extensive rotation of the frame with reference to the support can result in complete separation of the frame and canopy from the support so that the canopy descends toward or onto the ground. This can cause damage and/or injuries if the canopy is spread out above a table in an outdoor restaurant, above an outdoor food, fruit, flower or other stand or above a beach chair.
German Pat. No. 34 40 493 discloses an umbrella wherein a spherical joint which is directly carried by the overhead support is non-separably connected with the canopy-carrying frame. Such connection prevents total separation of the frame and canopy from the support; however, the connection also prevents convenient intentional detachment of the frame and canopy from the support, e.g., for overnight storage or in anticipation of heavy rains or strong winds. If the connection between the overhead support and the canopy carrying frame is located at a considerable distance from the ground, the person in charge of detaching the frame must resort to a chair, to a ladder or another implement which enables such person to reach and disengage the connection. The same procedure must be carried out in reverse when the frame is to be reattached to the overhead support.
In accordance with another prior proposal, the canopy carrying frame is mounted on an externally threaded spindle extending into a nut which is rigid with the spherical joint on the overhead support. The joint includes a socket and a spherical head in the socket. The latter is provided with a slot which receives an extension of the spherical head and thus permits attachment of the head to, or its detachment from, the socket. Separation of the head from the socket is possible only when the spindle is rotated relative to the nut to an extent which is necessary to move the frame to a position at a considerable distance from the spherical joint so that the head can be lifted above and its extension can be slipped out of the slot of the socket. A person standing beneath the frame and attempting to rotate the spindle with reference to the nut cannot observe the nut, i.e., such person cannot ascertain whether or not the spindle actually rotates relative to the nut in a direction to lower the frame and ultimately permit separation of the spherical head and its extension from the socket. If such person fails to terminate in time rotation of the spindle relative to the nut, the spindle becomes completely separated from the nut and the frame with the canopy is free to descend by gravity. This can result in damage to the frame and/or canopy as well as in injuries and in damage to the objects beneath the umbrella. Return movement of the frame and canopy to their operative positions is equally cumbersome. If a safety device is provided, such device must be actuated by hand prior to separation of the frame from the joint and again subsequent to reattachment of the frame.